Calcium Sulfate Precipitation in the Presence of Nondominant Calcium Carbonate: Thermodynamics and Kinetics
Calcium Sulfate Precipitation in the Presence of Nondominant Calcium Carbonate: Thermodynamics and Kinetics
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DOI：
10.1021/ie000781c
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发表时间：
2001-06
影响因子：
4.2
通讯作者：
R. Sheikholeslami;M. Ng
中科院分区：
文献类型：
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作者：
R. Sheikholeslami;M. Ng
本研究以共沉淀无机盐之方式探讨热交换器之污垢。研究了非优势CaCO 3对CaSO 4沉淀热力学和动力学以及垢结构的影响。尽管沉淀盐在工业水系统中共存，但由于结垢过程的复杂性，研究主要集中在单一的盐沉淀上。此外，所有的热力学预测模型和软件都只考虑了共存盐通过德拜-休克尔的离子强度或其修正形式的影响。本研究的结果表明，与共同离子的共沉淀盐的存在下影响的盐的溶解度常数，因此，在一个单一的盐沉淀下获得的溶解度数据的应用是值得怀疑的共同离子的共沉淀盐。同时，共离子的存在对沉淀动力学也有影响，传统的动力学分析方法不能适用于此。
This study addresses the fouling of heat exchangers by coprecipitating inorganic salts. It investigates the effects of nondominant CaCO3 on thermodynamics and kinetics of CaSO4 precipitation as well as on scale structure. Even though precipitating salts coexist in industrial water systems, because of the complexity of the fouling process, research has primarily been concentrated on a single salt precipitation. In addition, all thermodynamic predictive models and softwares only consider the effect of coexisting salts through the ionic strength by Debye−Huckel or modified forms of that. The results of this investigation indicate that the presence of a coprecipitating salt with a common ion affects the solubility constants of the salts, and therefore application of the solubility data obtained under a single salt precipitation is questionable for coprecipitating salts with common ions. Also, the kinetics of precipitation is affected by the presence of a common ion, and the traditional method of kinetic analy...